Yeah I'll quote myself from the Smash thread (if that's alright)
I get Sakurai's desire to make an accessible game and I agree with it as an aim. I don't understand his reasoning regarding pace, though. What makes other fighters difficult is the complexity of controls and needing to be quicker with your reactions by frame than your opponent.
In Smash, even in melee, anyone can pick up the game, jump around and do some special moves. When you've got those basic controls down, you know the basics of every single character. Items and luck can then easily keep a casual player in the game, unless you're doing the classic No Items, Final Destination shit (that I personally hate).
Once the game is that accessible, I'm not sure what slowing it down so much does. The only time that a casual will really be disadvantaged by a much faster paced game is 1v1 against a pro player, and that's a hugely unlikely scenario for me and the vast majority of casuals who play the game.
I'm a casual, and Smash is for casuals, and it should always be as accessible as possible as a priority, but I simply think a slower paced smash is less fun for everyone.